YY 0678-2008Standard performance and safety specification for cryosurgical medical instruments (English PDF)

3.1 Closed cryotip

a hollow, closed end usually shaped to fit a particular anatomical site where the cryogen cools the external surface which is applied to the target tissue.

3.2 Open cryotip

a device specifically designed to apply the cryogen directly to the target tissue.

3.3 Cryoprobe

the instrument used to deliver the cryogen to the cryotip or open tip. For a cryotip, a cryoprobe also directs the cryogen away from the target tissue.

3.4 Cryosystem

all parts of a system excluding the cryogen and its container, unless supplied by the manufacturer, that is designed to apply or use a cryogen.

3.5 Compressed gas cylinder

a container that is specifically designed to store a gas or liquid under elevated pressure conditions.

3.6 Compressed gas cylinder connector

a device specifically designed to attach to a cylinder for proper and safe removal of its contents.

3.7 Withdrawal device

connected device specially designed to make the cryogen in the container be released as required.

3.8 Cryogen

a substance used to obtain reduced temperatures.

Note: Cryogens are usually classed by their boiling points. The most common cryogens and their respective boiling points are as follows.

- Fast thermal thermocouple sensor.

- Temperature indicator or chart recorder.

- Other components, to make the cryosystem functional in accordance with the manufacturer's operational instructions. b) Sampling.

- For limited production or a unique cryosystem, perform and record a series of three freeze modes.

- For cryosystems of the same model, test and record three individual systems. c) Procedure.

- Attach the thermocouple sensor to the therapeutic surface of the cryotip as determined by the manufacturer.

- Immerse the closed cryotip into the simulated tissue model in a way which stimulates the intended application as determined by the manufacturer.

- Follow all parameters as described in the manufacturer's operational instructions to make cryosystem functional.

- Allow the cryotip to defrost between cycles.

- Include disposable devices.

- A pre-cycle for the cryosystems to normalize operating conditions is permitted.

- Calculate the reference temperature and limits of deviation from the recorded data. d) Conformance.

4.3 Tractive Force of Closed Cryotip

All the Cryosystem specially designed for cryoadhesion shall be able to lift weight of 60g at least in adhesion for at least 45 minutes. manufacturer may label his product as conforming to this Standard only if the product fulfills the requirements of this specification.

5.2 Disclosure

A manufacturer shall disclose each specification listed, where applicable.

5.2.1 A manufacturer of a cryosystem shall provide a warning statement to inform the user where contact with the cryosystem may cause user/patient harm. This statement shall appear in the instrument's instruction manual and, if possible, on sections of the instrument that become 0°C or colder.

5.2.2 A cryosystem designed to spray a cryogen onto a target tissue must have a disclosure statement warning the user to provide adequate protection to himself and the patient due to excess or residual cryogen droplets or mist.

5.2.3 A disclosure statement shall be required that states the normal operating pressure at +20°C, the boiling point, and the type of cryogen for which the instrument is designed.

5.2.4 A disclosure statement that states exactly what items of the cryosystem and its accessories can be sterilized and the recommended sterilization procedures shall be included with each cryosystem.

5.2.5 A disclosure statement shall be included with each pre-sterilized cryosystem.

a) Sterile;

b) The expiration date of sterilization;

c) Notes of caution concerning means of shipping, storage and use of the instrument.

5.2.6 All ac powered cryosystems and accessories shall be prominently labeled "Danger-Explosion Hazard. Do Not Use in Presence of Flammable Anesthetics".

5.2.7 The following information shall be included in the disclosure statement for tissue temperature monitors.

b) Temperature range. minimum to maximum,

c) Type of thermocouple (for example, Type "T"),

d) Temperature and humidity limits for storage, shipping and operation, and e) Power requirements.

c) Set up;

d) Use;

e) Dismantle;

f) Calibrations; g) Intended Applications.

5.4.2.1 Specifications - Cryosystem and Cryogen

a) Size;

b) Weight;

c) Type(s) of Cryogen(s) Used;

d) Minimum and Maximum Operation Pressure;

e) Power Requirements;

f) Temperature Control Description;

g) Cryosystem and Cryoprobe Performance Check

b) Defrost Features;

i) Temperature Sensor;

j) Serviceable Parts;

k) Manufacturer's Recommended Cryogen Containers;

l) Thermal Insulation;

m) Specifications - Cryogen Container.

5.4.2.2 Recommended Withdrawal Devices

a) Type(s) of Cryogen Employed;

b) Size;

c) Weight;

d) Capacity;

e) Static Hold Time. Container Only;

f) Static Hold Time. Container and Withdrawal Device;

g) Optimum and Maximum Operating Pressure;

h) Rating on Pressure Limiting Device;

i) Filling Directions; j) Serviceable Parts.

5.4.3 Servicing Instructions

a) Trouble-Shooting Chart;

b) Cryogen Flow Chart;

c) Electrical Schematics;

d) User Serviceable Parts List;

e) Preventive Maintenance Recommendations; f) Warranty Information.

5.4.4 Electrical and Cryogen Safety Instructions

a) User Related; b) Patient Related.

6.1 General

These cryosystem safety requirements are intended to protect the user and patient from harm during the use and storage of the cryosystem. […]